This study aimed to evaluate the association between the extracranial and intracranial calcification depiction of the internal carotid artery (ICA), incidentally found in CBCT examinations in adults, and to discuss the conspicuous clinical implications. Out of a series of 1085 CBCT examinations, 705 CBCT scans were selected according to pre-defined criteria. The extra- and intracranial calcifications depicted along the course of the ICA were documented according to a comprehensive set of descriptive criteria. In total, 799 findings were detected, 60.1% (n = 480) were intracranially and 39.9% (n = 319) were extracranially allocated. The χ(2) test showed associations between all variables (p < 0.001). Also, most of the combinations of variables showed statistically significant results in the McNemar's test (p < 0.001). We found that a significant correlation exists between extra- and intracranial calcifications of the ICA. It is clear that in cases of the presence of a calcification in the ICA extracranially, the artery's intracranial portion has an increased risk of showing the same findings. CBCT imaging is widely used as a diagnostic tool, thus, our results contribute to the identification of a subgroup of patients who should undergo further medical evaluation of the atherosclerosis of the ICAs.

The Index of Complexity, Outcome and Need (ICON), based on international opinion, has been proposed as a multipurpose occlusal index. The aim of this study was to validate the ICON for treatment need in the Netherlands by relating it to Dutch orthodontic opinion. Furthermore, the reliability of this index was explored, for both a calibrated orthodontist and non-calibrated orthodontists. A sample of 102 patients was chosen which represented the actual distribution of severity of malocclusion experienced by orthodontists in every day practice. The ICON was scored, based on complete patients records of those 102 patients, by an examiner calibrated in the use of this index. The results were compared with the opinion about treatment need of seven Dutch orthodontists – the ‘gold standard’. Nine non-calibrated orthodontists also scored the ICON for 49 patients. The intra-examiner agreement of both the non-calibrated and the calibrated orthodontists was moderate to high [0.52–0.86 and 0.89, respectively, measured with the Intraclass Correlation Coefficient (ICC)]. The inter-examiner agreement of the ICON score of the nine orthodontists was moderate measured with the single estimate of the ICC (0.60), and high measured with the average estimate (0.93). Spearman's correlation coefficient between the ICON score (calibrated) and the gold standard was sufficient: 0.78. The sensitivity and specificity were 1 and 0.36, respectively. The best compromise between sensitivity and specificity was at a cut-off point of 52, instead of the international ICON cut-off point of 43. There was a significant difference in ICON score between the non-calibrated orthodontists and the calibrated orthodontist, mainly based on the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). It can be concluded that the ICON needs to be adjusted when used to determine treatment need in the Dutch orthodontic population.

General dental practitioners (GDPs) act as gatekeepers for specialist dental care since they generally decide whether, when, and where to refer patients. It is important for orthodontists to understand the factors influencing the referral decision in order to be able to satisfy both the referring dentists and the patients. A specifically designed questionnaire was sent to a random sample of 634 GDPs in The Netherlands. In part A, general characteristics of the GDPs such as gender, years in practice, number of patients in the practice, possibilities to refer to an orthodontist, and number of patients referred to the orthodontist per year were collected. Part B assessed the importance of 20 various factors related to the GDPs’ usual referral decision. Intraclass correlation coefficients (ICC) were calculated to assess the relationship in rank scores of the items of the various groups. The response rate was 60 per cent. Most GDPs (38 per cent) had the possibility to refer to three to four orthodontists, 22 per cent could choose between five and six, and 21 per cent could refer to one or two. Most GDPs (55 per cent) actually referred to one to two orthodontic specialists, while 34 per cent choose between three and four orthodontists. The rank order of the items for male and female dentists was nearly equal (ICC = 0.99, P < 0.001). The most important factors governing the choice of an orthodontic treatment provider by GDPs were patient satisfaction, favourable experience in the past, and oral hygiene monitoring by the orthodontist.